<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>编组选择器</title>
    <style>
        h1, h2, h3, .box, #box, #out, #title {
            color: red;
            font-size: 50px;
        }
    </style>
</head>
<body>
<h1>极客学院</h1>
<h2>极客学院</h2>
<h3>极客学院</h3>
<div class="box">web</div>
<p id="box">Web前端</p>

<div id="out">
    <div id="title">Title</div>
</div>
</body>
</html>